Most of us exercise because we want to:
1) Lose Fat
2) Build or Tone (maintain) lean muscle
The exercise question I have seen debated over the years is the order you should perform your cardio/aerobic exercise and resistance training if your goal is fat loss.
I have heard the argument you should do your cardio before using the weights because it will warm up your body. I have also heard the debate that if your goal is to increase endurance and stamina you should do cardio before your weights. These are both reasonable debates.
I agree with the first debate you should warm up your body before doing weights. However, that doesn’t mean long or intense aerobic exercise is the most efficient way to warm up your body and prepare it for weight training. I do however recommend a very light 2-5 minute cardio warm-up followed by some dynamic (moving stretches) stretches before doing weight training. This will get your body’s blood flowing and muscle warmed up to prepare it for using resistance and lifting weight.
If your goal is endurance and stamina doing cardio before weights will give you more energy for that cardio session. However, doing weights after long or intense cardio is not an effective way to build strength or lose fat and in my opinion it’s counterproductive and a mistake.
If you’re running marathons or training for endurance races then weight training can help you with endurance and performance. However, I wouldn’t recommend even doing weights and cardio back to back. I would recommend either doing them on separate days or doing those 6 hours apart. This will allow you to get the full benefits of both without risking energy/strength crashes or risk of muscle loss.
Getting back to why most people are doing resistance training and cardio in the first place is to build muscle and burn fat.
If fat loss and building muscle is your goal then the order you do weight training and cardio is crucial for seeing the best and most efficient results.
Let’s look at the science of what happens and what fuels sources your body uses during weight and cardio sessions.
During aerobic exercise there is a lot of oxygen present and you can use two things as a fuel source stored sugar (glycogen) or fat.
During strength training even though oxygen is present your body doesn’t need it to perform this activity because your blood vessels are constricted and oxygen is not being used very much if at all. Therefore during strength training you can NOT use fat as a fuel source it is not an option so you can only use glycogen.
If you are doing aerobic/cardio exercise first you will burn mostly glycogen as its your body’s preferred source of fuel. Follow with weight training and there is much less glycogen to burn therefore muscle will become a source of fuel once the workout becomes intense.
However, if you flip that and you do your resistance training first you will use your stored glycogen for energy (which is your only option) follow it with cardio now your body’s only remaining option is fat.
In simple your body will use much more fat for a fuel source doing cardio after weight training than doing it before.
Does this mean people can’t lose fat or see results doing cardio before weights? No, it just means it’s not the most efficient way and your workouts have a much greater chance of being more effective and productive by doing resistance training first. I always tell my clients it’s not always about training harder or longer but training smarter. Making things more difficult when you don’t need to and doing something that can be less effective in regards to someone seeing the best results will always be a mistake in my opinion.
So I would recommend the following in regards to doing weights and cardio:
1) Do weight training and cardio on completely separate days
2) If your goal is fat loss and building/maintaining lean muscle mass and you want to do them back to back always do your resistance training before cardio. Also, try to keep your cardio to a maximum of 30 minutes after weights.
3) Separate your weight training and cardio sessions 6 hours apart. This will allow some muscle recovering and allow you to refuel your body.
4) Have a proper supportive meal a 60-90 minutes before exercise and proper meal/recovery shake within 30 minutes after exercise. This will allow energy for your body and will assure you have plenty of fuel for your workouts and not risk using muscle for energy over time.
Your Fitness and Nutrition Coach,